Entrainment is a principle of physics which appears in biology, chemistry, neurology, medicine, astronomy etc. It is defined as the synchronization of two or more rhythmic cycles. In the seventeenth century, Dutch scientist Christian Huygens found out that by placing two unsynchronized clocks side by side on a wall, they would slowly synchronize to each other in a very accurate way. The clocks were the first example of spontaneous synchronization, a phenomenon found throughout nature from cells to the Solar System.
Alpha (12hz – 8hz) – Awake, but deeply relaxed. Simply closing your eyes will produce alpha brainwaves. This category is associated with daydreaming, visualization, imagination, light meditation. Brainwave expert Anna Wise called the alpha range the bridge between beta and theta. (More information can be found in Wise’ book The High-Performance Mind)
Nothing is more stressful than being unprepared. Get organized so you're ready for the next day, taking a few minutes to make a to-do list and clean up before you leave. Knowing you've got everything covered means you'll be less likely to fret about work in the evenings. When you come in the next morning, you'll have the sense that you're in control of the situation and can handle it. This sets a positive tone for the day, which can help you get more accomplished. (You can even turn your nightly beauty routine into a stress-relieving practice.)

Both brainwave entrainment and neurofeedback deal with brainwaves, but the similarity stops there. Entrainment pushes your whole brain into a pre-determined state, while neurofeedback teaches you how to move specific parts of your brain on your own. It is the differeence between forcing the brain into a given position, and skills building so you can move it there yourself.